Modular material handling system for order fulfillment

ABSTRACT

Methods and apparatus for material handling in an order fulfillment center. An order fulfillment system may include inventory storage, a processing area, and a control system. The inventory storage may in some instances include two storage areas, and in some cases the processing area may be disposed between the two storage areas. The processing area may include a router module that is configured to receive inventory items that have been picked from the inventory storage. Inventory items may be received by the router module via conveyance receptacles (e.g., totes, bins) that are conveyed using a conveyor mechanism. The processing area may also include a plurality of processing modules that may be configured to receive inventory items from the router module. In some instances, the processing modules may receive the inventory items via conveyance receptacles that are conveyed using the conveyor mechanism.

This application is a continuation of U.S. patent application Ser. No. 13/280,134, filed Oct. 24, 2011, now U.S. Pat. No. 8,892,240, which claims benefit of priority to U.S. Provisional Patent Application No. 61/502,790, filed Jun. 29, 2011, both of which are incorporated herein by reference in their entireties.

BACKGROUND

In a distribution system, a retailer or other product distributor (which may collectively be referred to as distributors) typically maintains an inventory of various items at one or more distribution centers, fulfillment centers, cross-docking facilities, materials handling facilities or warehouses (which may collectively be referred to as materials handling facilities). The inventory items are ordered from one or more vendors, received at the materials handling facilities as inbound shipments, and stocked in inventory of the materials handling facilities. In a conventional order fulfillment process, orders for items may be received from customers of the distributor. Units of the ordered items are picked from various locations in the inventory in the materials handling facilities, processed for shipping, and shipped as outbound shipments to the customers.

The facilities operated by the merchant may include various fulfillment processes for fulfilling orders submitted by customers. These processes may operate on items to perform various tasks, such as preparing items for shipment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a logical representation of various operations of a materials handling facility, according to some embodiments of the present disclosure.

FIG. 2 illustrates an example of a high-level physical layout of a materials handling facility, according to some of the present embodiments.

FIG. 3 depicts an example of a control system that may be employed in some embodiments.

FIG. 4 illustrates an exemplary physical layout of a materials handling facility, according to one of the present embodiments.

FIG. 5 illustrates operation of an exemplary sorting station that may be used in processing modules of some of the present embodiments.

FIG. 6 is a flowchart illustrating a method of operation of one of the present embodiments.

FIG. 7 is a flowchart illustrating various aspects of one present embodiment.

FIG. 8 is a block diagram illustrating an example computer system that may be used in at least some embodiments of the present modular material handling system.

Specific embodiments are shown by way of example in the drawings and will be described herein in detail. It should be understood, however, that the drawings and detailed description are not intended to limit the claims to the particular embodiments disclosed, even where only a single embodiment is described with respect to a particular feature. On the contrary, the intent is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. Examples of features provided in the disclosure are intended to be illustrative rather than restrictive unless stated otherwise.

The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). The words “include,” “including,” and “includes” indicate open-ended relationships and therefore mean including, but not limited to. Similarly, the words “have,” “having,” and “has” also indicate open-ended relationships, and thus mean having, but not limited to. The terms “first,” “second,” “third,” and so forth as used herein are used as labels for nouns that they precede, and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.) unless such an ordering is otherwise explicitly indicated.

Various components may be described as “configured to” perform a task or tasks. In such contexts, “configured to” is a broad recitation generally meaning “having structure that” performs the task or tasks during operation. As such, the component can be configured to perform the task even when the component is not currently performing that task (e.g., a router module may be configured to receive inventory items, even when the items are not currently being received). In some contexts, “configured to” may be a broad recitation of structure generally meaning “having circuitry that” performs the task or tasks during operation. As such, the component can be configured to perform the task even when the component is not currently on. In general, the circuitry that forms the structure corresponding to “configured to” may include hardware circuits.

Various components may be described as performing a task or tasks, for convenience in the description. Such descriptions should be interpreted as including the phrase “configured to.” Reciting a component that is configured to perform one or more tasks is expressly intended not to invoke 35 U.S.C. §112, paragraph six, interpretation for that component.

DETAILED DESCRIPTION OF EMBODIMENTS

Various embodiments of methods and apparatus for material handling in an order fulfillment center, using a modular material handling system are described. In some of the described embodiments, an order fulfillment system includes inventory storage, a processing area, and a control system. The inventory storage may in some instances include two storage areas, and in some cases the processing area may be disposed between the two storage areas.

In some embodiments, the processing area may include a router module that is configured to receive inventory items that have been picked from the inventory storage. In some cases, the inventory items may be received by the router module via conveyance receptacles (e.g., totes, bins) that are conveyed using a conveyor mechanism, where the conveyance receptacles are not fixed to the conveyor mechanism. The processing area may also include a plurality of processing modules that may be configured to receive inventory items from the router module. In some instances, the processing modules may receive the inventory items via conveyance receptacles that are conveyed using the conveyor mechanism. In some cases, the processing area may also include a shipping module that is configured to receive packaged inventory items from various ones of the processing modules.

Some embodiments of the present disclosure further include a control system that is operable to cause a particular inventory item to be picked from the inventory storage and to be routed (e.g., via the conveyor mechanism) to the router module of the processing area. Various embodiments include a control system that is further operable to cause the router module to route the particular inventory item to a selected processing module that may perform packaging operations for the particular inventory item. The selected processing module may in some cases be selected based at least in part on the received customer order. For example, a certain processing module may be required if the particular inventory item was part of a multi-item customer order, as opposed to a single-item customer order.

Various embodiments may include a control system that is operable to determine one or more inventory storage zones for storing a replenishment supply of an inventory item. These inventory storage zones may be determined based at least in part on various optimization criteria (e.g., throughput, cost, storage density). In some cases, pick-to-ship time is minimized. In some cases, receive-to-stow time is minimized.

The various operations of a materials handling facility may be located in one building, or alternatively may be spread or subdivided across two or more buildings. In addition, a materials handling facility may include one or multiple levels or floors. For example, a materials handling facility that includes inventory 30 may include one, two, or more levels; in multi-level facilities, inventory 30 may be spread across two or more levels. The total floor space of a materials handling facility may be anywhere from tens of thousands of square feet to more than a million square feet, although embodiments may be implemented in smaller facilities.

FIG. 1 illustrates a logical representation or view of the operation of a materials handling facility in which embodiments of the modular material handling system may be implemented. For example, this figure may illustrate an order fulfillment center of a product distributor. Multiple customers 10 may submit orders 20 to the product distributor, where each order 20 specifies one or more items from inventory 30 to be shipped to the customer that submitted the order. To fulfill the customer orders 20, the one or more items specified in each order may be retrieved, or picked, from inventory 30 (which may also be referred to as stock storage) in the materials handling facility, as indicated at 40. Picked items may be delivered or conveyed, if necessary, to one or more stations in the materials handling facility for sorting 56 into their respective orders, packing 60, and finally shipping 70 to the customers 10. In some embodiments of the modular material handling system, picked items may be delivered to a singulation station, where individual units of items are associated with and placed into particular conveyance receptacles, which are then inducted into a conveyance mechanism. The conveyance receptacles may then be routed to particular destinations for the items contained within the receptacles in accordance with the requests (orders) currently being processed, e.g. to sorting stations, under direction of a control system. A picked, packed and shipped order does not necessarily include all of the items ordered by the customer; an outgoing shipment to a customer may include only a subset of the ordered items available to ship at one time from one inventory-storing location. In some other embodiments, picked items may be delivered to particular destinations via other means, such as automated guided vehicles, pallet jacks, etc.

The picking process 40 as illustrated in FIG. 1 may be implemented in two or more different inventory areas, for example on different floors or in different areas of a materials handling facility. Two or more separate stock storage areas may be maintained and may be physically located on different floors of a materials handling facility. For each separate stock storage area, there may be one or more associated induction stations. Types of items may be, but are not necessarily, stored in different stock storage areas. For example, units of a given type of item may be stowed to locations in storage units in both inventory areas.

A materials handling facility may also include a receiving 80 operation for receiving shipments of stock from one or more sources (e.g., vendors) and for placing the received stock into stock storage. The receiving 80 operation may also receive and process returned purchased or rented items or orders from customers. At least some of these items are typically returned to inventory 30. The various operations of a materials handling facility may be located in one building or facility, or alternatively may be spread or subdivided across two or more buildings or facilities. In various instances, it should be understood that references to elements, units, items, processes (or anything else) as being located within materials handling facility 100 may easily be extended to encompass elements, units, items, processes (or anything else) proximate to but not physically located within materials handling facility. For example, various elements, units, items, or processes (or anything else) may be implemented outside of the materials handling facility, according to some embodiments.

FIG. 2 illustrates an example of a physical layout of a materials handling facility, such as an order fulfillment facility or center, in which embodiments of the modular material handling system may be implemented. At any one time, one or more agents 42 of the distributor may each be picking items from inventory 30 to fulfill portions or all of one or more requests or orders. This may result in a stream and/or batches of picked items for multiple incomplete or complete orders, which may then be delivered to an induction station (e.g., at routing module 52 or elsewhere within processing area 50). For example, in some instances, picked items in conveyance receptacles (e.g., totes), each containing one or more units of items (each possibly containing items from two or more orders) may be conveyed to any of various inductions stations that may be present, via a conveyance device (e.g., a conveyor belt). In other embodiments, picked items may be conveyed via other means. For example, large items may require transport via pallet jacks or other larger form factors.

At an induction station, each item may be pulled individually from each conveyance receptacle. Alternatively, all items may be “dumped” into a common receptacle (a bin, basket, shelf, etc.), and individual units may then be pulled from the common receptacle. In various embodiments, each pulled unit is then placed into a conveyance receptacle (e.g., a tote or tray) by itself. This process may be referred to as singulating the item. Receptacles, as used herein, may include, but are not limited to, any tote, basket, box, tray, or similar mechanism configured to receive individual units of items or groups of units of items in a materials handling facility. A conveyance receptacle need not be fixed to any conveyance mechanism.

The pulled unit of an item may be associated with the particular conveyance receptacle that it is placed in. In one embodiment, the association of a unit of an item with a particular conveyance receptacle may be performed by reading, scanning or otherwise entering an item identifier associated with the item and a conveyance receptacle identifier associated with the particular conveyance receptacle into which the unit is placed. The item identifier and receptacle identifier may be communicated to a control system 190 of the materials handling facility via wired and/or wireless communications. Each conveyance receptacle may include a unique conveyance receptacle identifier that uniquely identifies the particular conveyance receptacle in the materials handling facility. The conveyance receptacle identifier may, for example, be indicated by a bar code, QR code, Radio Frequency Identifier (RFID) device, or some other scannable or readable mechanism, mark, or tag attached to or integrated with the conveyance receptacle.

Each unit of each item carried in inventory 30 may include an item identifier. A type of item held in inventory 30 may be referred to herein as simply an item. The term item identifier may refer to a unique identifier associated with each particular type of item carried in inventory 30 of a distribution system. The term unit may be used to refer to one (unit) of a type of item. Typically, but not necessarily, each unit is tagged or otherwise marked with the item identifier. For example, units or collections of items in inventory may be marked or tagged with a bar code, Universal Product Code (UPC), Stock-Keeping Unit (SKU) code, serial number, and/or other designation (including proprietary designations) that may be used as item identifiers to facilitate materials handling facility operations, including, but not limited to, stowing, rebinning, picking, sorting, packing and shipping. These designations, or codes, may identify items by type, and/or may identify individual units within a type of item.

Cases, boxes, bundles, or other collections of units of items may similarly be marked or tagged with item identifiers. The units of items in a collection may all be of the same type of item, for example a case of twelve units of a particular item, or may be a collection of one or more units of each of two or more heterogeneous items. A collection of units of item(s) (e.g., a case containing twelve units of an item, or a bundle containing one or more units of each of two or more heterogeneous items, such as a boxed or bundled set of three different books) may thus be considered or treated as a “unit” in the order fulfillment process. A designation, or code, may thus also identify a collection of units of item(s) as a “unit” in the order fulfillment process. Thus, various, in addition to sorting individual units of items, may also process collections of units of item(s) designated as units. Therefore, the conveyance receptacles described herein may receive collections of units of item(s) that are designated as units as well as individual units of items.

A materials handling facility may include a control system 190 which may include, but is not limited to, one or more computer systems, one or more data storage devices, one or more wired and/or wireless networks, control system software (programs, modules, drivers, user interfaces, etc.), and one or more hand-held, mobile and/or fixed readers, scanners or scanning devices that may be able to scan, receive, or otherwise detect the marks or tags (e.g., bar codes, radio frequency identification (RFID) tags, etc.) on individual items (units) or collections of items (e.g., cases) and communicate with a control station or stations of the control system to, for example, determine and record the item and/or item type of the items. The hand-held, mobile and/or fixed readers, scanners or scanning devices may also be able to scan, receive, or otherwise detect the marks or tags (e.g., bar codes, radio frequency identification (RFID) tags, etc.) attached to or integrated with the conveyance receptacles. An exemplary computer system that may be used in a control system 190 is illustrated in FIG. 8. An exemplary network topology that may be used in control system 190 is shown in FIG. 3.

At the induction station, a pulled unit of an item may be associated with a particular conveyance receptacle by reading, scanning, etc. the item identifier associated with the item and the conveyance receptacle identifier associated with the conveyance receptacle into the control system 190. This may be performed manually (e.g., by an operator or agent using a hand-held scanner), via an automated scanning/reading process using fixed scanners/readers, or by a combination of manual and automatic scanning/reading. For example, an operator at an induction station may use a hand-held scanner to scan a code off the unit of the item before or during placement of the unit into a “staged” conveyance receptacle, while an automated reader may read (or may have already read) the conveyance receptacle identifier from the new conveyance receptacle that is “staged” for the operator to place the unit of the item into.

Once a pulled unit of an item is associated with and placed into a particular conveyance receptacle, that conveyance receptacle may be inducted into a conveyance mechanism (e.g., a conveyor belt, roller system, or other conveyance mechanism). In various embodiments, the conveyance mechanism may include a mechanism that includes some method of diverting a product off a conveyance path under control of the control system. Examples of such diversion mechanisms may include, but are not limited to, sliding shoe sorter mechanisms and pop up diversion mechanisms, such as pop up wheel sorter mechanisms. A pop up wheel sorter includes powered wheels that rise up out of the conveyor to divert product off the conveyor onto a different path or to a location. Other types of mechanisms may be used in various embodiments.

A conveyance receptacle may already be on the conveyance mechanism when the unit is associated with and placed into the receptacle. Alternatively, a conveyance receptacle may be retrieved from a conveyance receptacle storage, stack, or other supply, the unit may be associated with and placed into the receptacle, and the receptacle may then be inducted into or placed on the conveyance mechanism. The conveyance receptacles need not be fixed to the conveyance mechanism; instead, the receptacles may be removable bins, trays, totes, or similar devices. The conveyance mechanism may be coupled to and controlled by the materials handling facility control system 190 via wired and/or wireless communications. The control system 190 may receive input from and send commands to the conveyance mechanism to direct or control various operations of the conveyance mechanism.

The above describes aspects of an induction station 210 in which a human operator performs at least a portion of the pulling of units of items from groups of picked items, scanning/reading the items and receptacles to associate single units of items to particular conveyance receptacles, and placing the units into the conveyance receptacles. In alternative embodiments, some or all of the activities described as being performed by a human operator may be performed by automated mechanisms, which may be coupled to and under control of the materials handling facility control system 190.

The conveyance mechanism, under direction of control system 190, may deliver the conveyance receptacles, each including an individual unit of an item, to various order processing modules 55. Various ones of the processing modules 55 (or elsewhere in processing area 50) may include one or more sorting stations. Portions of an order may be received from the agents 42, or from other stations, at a processing area 50 at different times. Thus, processing at a station may have to wait for one or more items for some orders to be delivered to the station from picking and/or from another station before completion of processing of a multi-item order at the sorting station.

The picked units of items that in some cases are delivered to a processing area via the conveyance receptacles may be processed at routing module 52. For example, routing module 52, under the direction of control system 190, may in some embodiments sort the individual picked units in accordance with their respective orders. In other embodiments, the picked units may be sorted into their respective orders at one or more of processing modules 55 under the direction of control system 190. As discussed in greater detail below, various processing modules 55 may provide differing types of packaging operations that may be suitable for differing picked items (e.g., based on the size of the item), or differing order category (e.g., multi-item orders, single-item orders)

An order fulfillment center may also include one or more receiving 80 operations for receiving shipments 90 of stock from various vendors. The received stock may then be placed into stock storage. The receiving 80 operation may also receive and process returned, purchased, or rented items from customers. The various operations and stations of an order fulfillment center may be located in one building or facility, or alternatively may be spread or subdivided across two or more buildings or facilities.

Turning now to FIG. 3, one exemplary embodiment of control system 190 is depicted. Control system 190 may in some cases include a host warehouse management system (Host WMS) in coordination with various localized control system components, such as one or more warehouse control systems (WCS), sensors, conveyor-specific controllers (e.g., programmable logic controllers), and other motion-control components. For example, the Host WMS may in some embodiments provide high-level instruction as to routing and scheduling of items to particular modules of the system, whereas the WCS may execute lower-level tasks related to execution of the routing and scheduling the conveyance of the inventory items in accordance with the routing dictated by the Host WMS (e.g., messaging proper zones within the modular material handling system). Other embodiments may include a more centralized configuration in which a central host oversees most or all of the material handling functions, of alternately a more distributed configuration in which most or all of the material handling functions are handed off between area-specific controller components.

Physical Layout of Modular Material Handling System

FIG. 4 presents greater detail of the physical layout of one embodiment of the present disclosure. In the depicted embodiment, processing area 420 is located between inventory areas 410 a and 410 b, with router module 422 of processing area 420 receiving/sending inventory items to/from each of inventory areas 410 a and 410 b via conveyor mechanisms. By virtue of this layout, which includes multiple smaller individual inventory areas distributed around the processing area, the maximum distances that picked inventory items must travel (e.g., from the farthest end of an inventory area to the router module of the processing area) are lower than distances that may be encountered in configurations having a single equivalent, larger inventory area (e.g., an inventory area having a volume equal to the combined volume of inventory areas 410 a and 410 b) located adjacent to the processing area. Accordingly, pick-to-ship times may be minimized by use of this physical layout. Other embodiments may provide similar benefits by use of more than two inventory areas disposed around a processing area. In some embodiments, multiple inventory areas may be located adjacent to various sides of processing area 420 in an asymmetric layout.

The physical layout of fulfillment center 400 depicted in FIG. 4 may further improve inventory item throughput by virtue of the availability of additional conveyance paths between processing area 420 and the two inventory areas 410 a and 410 b. For example, twice as many conveyor lines of a minimal length L between the two inventory areas and router module 422 may be possible in the embodiment of FIG. 4, as compared to an embodiment in which only a single inventory area is employed on one side of router module 422. In some embodiments, control system 190 may maximize material throughput by exploiting the availability of additional conveyance paths. For example, a high demand item may be stored in both inventory area 410 a and in the oppositely disposed inventory area 410 b to take advantage of the availability of a maximum number of conveyance mechanisms. In such a way, it may be possible to double the throughput of extremely high demand items.

The factory layout may provide additional opportunities for efficiency improvement, based on a more centralized distribution of personnel that may be achieved by the central location of processing area 420. For example, the greater concentration of operators due to centrally located processing area 420 may provide for more efficient management of those operators (e.g., via lower ratios manager to operator ratios).

Embodiments of fulfillment center 400 may include control system 190 that is configured to dynamically adjust inventory placement strategies as demands change. For example, it may initially be beneficial to store inventory of a particular low demand product at inventory area zones that are relatively distant from router module 422. Such an arrangement may allow higher demand items to be stored at inventory locations that are nearer router module 422. This may be desirable because an item at storage zone 412 a will have a longer pick-to-ship time than an item picked at storage zone 412 e). It may also be desirable for simplicity reasons to store the particular low demand product together at one particular storage zone 412 within inventory area 410.

Now consider a scenario in which demand increases dramatically for the above-discussed item. It may be beneficial to relocate the suddenly high-demand product to a more desirable area of the inventory areas (e.g., storage zone 412 e). If demand is exceptionally high, it may also be desirable to relocate the high demand product across multiple storage zones 412, in order to avoid possible backlog at conveyance mechanisms (e.g., due to excessive conveyance receptacles/totes overwhelming a particular conveyor line) and/or at a picking module. In such a case, relocating the high demand product to multiple storage zones (e.g., storage zones 412 e and 412 f of inventory area 410 a, as well as additional zones in inventory area 410 b) may eliminate the sources of backlog. Inventory items may be relocated within the inventory areas by use of, for example, bypass lines 414 a and 414 b, which route materials through router module 422.

Continuing with FIG. 4, router module 422 serves as the interface between inventory areas 410 and the various processing modules 426. As discussed above, router module 422 receives conveyed inventory items from pick modules within inventory areas 410. In some embodiments, the inventory items are received via conveyance receptacles (e.g., standardized totes) that are transported via conveyance mechanisms (e.g., conveyor lines). The conveyance receptacles may not be fixed to the conveyance mechanism in various embodiments. In some cases, other methods for conveying the inventory items are employed (e.g., various robotic form factors, automated guided vehicles). Control system 190 may govern the conveyance of the inventory items (e.g., via the a Host WMS and a supporting WCS) to router module 422, and the subsequent routing of inventory items to processing modules 426. Various identifying methods (e.g., RFID tags, barcode scanner, QR scanners located, for example, on the conveyance receptacles) may be employed to track the movement of the inventory items).

In some embodiments, router module 422 provides one or more standardized interfaces (e.g., physical conveyer interface, data interface, power interface) to various processing modules 426 that are coupled to router module 422 for receiving inventory items. These standardized interfaces may be expandable to accommodate varying numbers of processing modules 426. In this way, router module 422 may support flexible configuration of the type and number of processing modules 426 employed in a fulfillment center.

Various embodiments of router module 422 pass along received conveyance receptacles. In other cases, router module 422 may perform some redistribution (e.g., re-toting) of inventory items prior to conveying materials to one or more processing modules 426.

Processing Modules

Various processing modules 426 provide configurable functionality that may include processing and packaging inventory items and customer orders of various types. For example, FIG. 4 depicts a configuration of processing area 420 that includes three multi-item material handling system modules 426 a, four flex-pack modules 426 b, three auto-box modules 426 c, and two gift-wrap modules 426 d. These modules are configured in a modular manner to interface with router module 422 and shipping module 424.

Multi-item material handling system modules 426 a may provide capabilities for handling inventory items that are received in conveyance receptacles containing, for example, multiple inventory items corresponding to multiple customer orders. These inventory items may also correspond to customers orders containing multiple inventory items. FIG. 5 illustrates operation of an exemplary sorting station that may be used for assembling these multi-item orders in embodiments of multi-item material handling system modules 426 a, or in other processing modules 426 or router module 422 in some embodiments. Initially, conveyance receptacles containing multiple items are divided to single item conveyance receptacles 104. Once the conveyance receptacles 104, each containing an individual unit 108 of an item and each associated with the item it contains, are inducted into the conveyance mechanism 200, at least some of the receptacles 104 may be conveyed to sorting station 152. In one embodiment, the conveyance mechanism may be directed by the control system 190 as to the disposition of each particular conveyance receptacle 104. Each conveyance receptacle 104 may be associated with the particular item it contains. Thus, the control system 190 may, by tracking a particular conveyance receptacle 104 via its unique conveyance receptacle identifier 106, direct the conveyance mechanism to route the particular conveyance receptacle 104 and its associated unit 108 of the item to sorting station 152.

There may be one or more order processing stations 155 associated with sorting station 152. In this example, an order processing station 155 is located on the other side of order sorting bin 154. Order processing station 155 may, for example, be a packing station at which one or more units 108 of items for an order are processed, packed, and labeled for shipping to the customer. The order slots 156 may be pass-through slots into one side of which units 108 of items may be placed, and out of which individual or collections of units 108 of items may be removed for processing. In one embodiment, units 108 of items may be removed from conveyance receptacles 104 and placed into a particular slot (e.g., item 108 is illustrated as being placed into slot (3, 2)) as indicated by the control system 190, for example by the control system 190 activating an indicator 158 associated with the slot 156 into which the unit 108 is to be placed to indicate to the operator that the unit 108 from the current receptacle 104 is to be placed into that slot 156. Sorting bin 154 may also include indicators associated with the slots 156 on the order processing station 155 side which control system 190 may activate to indicate to operators at the order processing station 155 that a particular slot 156 is ready to be processed (e.g., that all units 108 of all items for an order have been placed into that slot). In this example, control system has indicated to operator(s) at order processing station 155 that an order 160 in slot (2, 1) has been completed. An operator may then pull the order 160 from the slot 156 for further processing (e.g., shipping).

Continuing with FIG. 4, flex-pack modules 426 b may provide functionality for processing items that are inappropriate for other processing modules 426 due to, for example, size and/or weight of the items. In some embodiments, an operator may remove a tote from the conveyor and places it on a work shelf to perform manual operations. Carts may be utilized to assist in processing large items.

Auto-box modules 426 c may provide for automated packaging of items conforming to certain particular dimensional constraints. In some cases, applicability of auto-box modules 426 may be limited to packaging of single-item orders. Other embodiment include auto-box modules 426 that may provide automated packaging of multi-item orders.

Gift-wrap modules 426 d may facilitate gift wrap of packages corresponding to customer orders requesting gift wrapping. In some embodiments, personnel may perform the required packaging as directed by the control system 190. However, in some embodiments automated wrapping of packaging conforming to particular dimensional constraints, similar to the auto-box modules 426 c, may be performed.

Continuing with FIG. 4, receiving modules 430 may be arranged in some embodiments to minimize receive-to-stow time. For example, multiple receiving modules 430 may be implemented to optimally correspond to the various inventory areas 410. These receiving modules may convey replenishment supply to replenishment sorter 440, that may serve to optimize storage of items (e.g., under control of control system 190) based on various criteria, such as minimization of pick and/or stow times.

In various embodiments, shipping module 424 may provide for sorting and/or routing of processed inventory items (e.g., packaged items) based on factors such as, for example, package type (e.g., flat packages, large crates, standard boxes, expedited delivery, cross-shipment of items to other fulfillment centers), and, in some cases, for further processing that may be required prior to shipment (e.g., verification of labeling). Some embodiments may include shipping modules 424 having various discrete modules that respectively correspond to one or more particular package types. As one example configuration, shipping modules 424 depicted in FIG. 4 may include flat package module 424 a for sortation of flat packages, carton module 424 b for sortation of standard cartons, and special handling module 424 c for sortation of items that may require custom handling (e.g., large items, items corresponding to expedited orders). In some other embodiments, a single shipping module 424 may be used for shipments of all package types processed by processing modules 426.

Shipping module 424 may include one or more standardized interfaces (e.g., physical conveyer interface, data interface, power interface) to various processing modules 426 that deliver processed inventory items to shipping module 424. These standardized interfaces may be expandable to accommodate configurations having varying numbers of processing modules 426. In this way, shipping module 424 may support flexible configuration of the type and number of processing modules 426 employed in a fulfillment center.

Various embodiment of the present disclosure may be configured to receive and process items from other fulfillment centers. As one example, a particular fulfillment center may receive cross-shipped items from one or more other fulfillment center to replenish stock of the particular fulfillment center. As another example, cross-shipped items may be received by the particular fulfillment center in order to complete an order that is processed at the particular fulfillment center (e.g., packaged as part of a multi-item order, packaged as a single-item order). In such cases, a cross-shipped item may be received and appropriately routed via, for example, one or more of a storage area, a routing module, a processing module, a shipping module, etc.

In some embodiments, the conveyance mechanisms may be configured to convey received items to a storage area for inventory replenishment purposes, deliver picked items from a storage area to the processing area for order processing, and for transporting empty conveyance receptacles to areas of need. For example, a particular conveyance mechanism, such as a conveyor, may be employed to perform each of the above-mentioned tasks of transporting items for storage and for processing, as well as transporting empty receptacles for from, for example, the packaging or shipping modules to the receiving module or inventory areas for further use.

FIG. 6 is a flowchart illustrating a method of operation in a modular material handling system for use in a fulfillment center, according to one embodiment. This flowchart illustrates how the various components described herein, such as a controller system, routing module, processing module, shipping module, inventory area, processing area, and processing modules, for example, may be integrated to form a modular material handling system for use a fulfillment center. The method as illustrated in FIG. 6 may be performed as a continuous or near-continuous process by modular material handling system to process incoming items for replenishment, or to process items picked from storage to fulfill customer orders.

At 602, an inventory item (e.g., inventory replenishment) may be transported from an inventory receiving area to a storage area of the fulfillment center. Transportation may be by way of a non-linear conveyor system (e.g., conveyance totes are not fixed to a conveyor, and therefore items need not be linearly delivered). In other embodiments, transportation may involve automated guided vehicles, robotics, manual transfer, etc. At 604, the item may be stored at the storage area (e.g., placed in inventory).

At 606, the inventory item may be picked from the storage area in response to a received order. For example, based on a customer's order for a particular item, that item may be picked from inventory. The picking may be performed using a computer system, and may also in some cases involve various automated picking systems. The picking process may be performed using a computer system that may, in some embodiments, optimize material throughput through methods that result in mixed groupings of items (e.g., items corresponding to different orders being grouped together).

At 608, the picked inventory item may be routed to one or more processing modules with the fulfillment center. The routing may be accomplished by way of the controller system and a routing module that may provide a standard interface to various processing modules. At 610, the picked inventory item may be processed using, for example, one or more modular processing modules that interface to the routing module and a shipping module. In some embodiments, the processing may be in accordance with various information corresponding to a customer order. For example, customer selection of gift wrapping with an order may result in processing of items in that order via a gift-wrapping module. As another example, customer selection of a group of various items within a single customer order may in some cases result in processing via one or more modules that facilitate combining multiple parts into a single shipment.

FIG. 7 presents a flowchart illustrating a method of operation in a modular material handling system that may be used to optimize inventory storage strategies. Such strategies may provide, for example, reduced receive-to-stow time and/or reduced pick-to-ship time. At 702, inventory storage locations (zones) within one or more inventory storage areas of a fulfillment center are determined. In some embodiments, this determination is based on minimizing distances that the item must be conveyed in order to stow or to subsequently pick and process the item. In some cases, the determination may estimate effects of the storage density of the particular item, or the storage density as to all items in the vicinity of the various storage zones. Storage densities may be meaningful because high storage density of high-demand items may increase probabilities that heavy pick activity or heavy stow activity within a localized area (e.g., the storage zone) may create bottlenecks.

Illustrative System

In at least some embodiments, a system that implements one or more components of modular materials handling system that implements the techniques described herein may include a general-purpose computer system that includes or is configured to access one or more computer-accessible media, such as computer system 800 illustrated in FIG. 8. In the illustrated embodiment, computer system 800 includes one or more processors 810 coupled to a system memory 820 via an input/output (I/O) interface 830. Computer system 800 further includes a network interface 840 coupled to I/O interface 830.

In various embodiments, computer system 800 may be a uniprocessor system including one processor 810, or a multiprocessor system including several processors 810 (e.g., two, four, eight, or another suitable number). Processors 810 may be any suitable processors capable of executing instructions. For example, in various embodiments, processors 810 may be general-purpose or embedded processors implementing any of a variety of instruction set architectures (ISAs), such as the x86, PowerPC, SPARC, or MIPS ISAs, or any other suitable ISA. In multiprocessor systems, each of processors 810 may commonly, but not necessarily, implement the same ISA.

System memory 820 may be configured to store instructions and data accessible by processor(s) 810. In various embodiments, system memory 820 may be implemented using any suitable memory technology, such as static random access memory (SRAM), synchronous dynamic RAM (SDRAM), nonvolatile/Flash-type memory, or any other type of memory. In the illustrated embodiment, program instructions and data implementing desired functions, such as those methods and techniques described above for a control system in a robotic induction technique and/or in a non-linear, unit-level materials handling system that implements the robotic induction technique, are shown stored within system memory 820 as code 825 and data 826.

In at least some embodiments, I/O interface 830 may be configured to coordinate I/O traffic between processor 810, system memory 820, and any peripheral devices in the device, including network interface 840 or other peripheral interfaces. In some embodiments, I/O interface 830 may perform any necessary protocol, timing or other data transformations to convert data signals from one component (e.g., system memory 820) into a format suitable for use by another component (e.g., processor 810). In some embodiments, I/O interface 830 may include support for devices attached through various types of peripheral buses, such as a variant of the Peripheral Component Interconnect (PCI) bus standard or the Universal Serial Bus (USB) standard, for example. In some embodiments, the function of I/O interface 830 may be split into two or more separate components, such as a north bridge and a south bridge, for example. Also, in some embodiments some or all of the functionality of I/O interface 830, such as an interface to system memory 820, may be incorporated directly into processor 810.

Network interface 840 may be configured to allow data to be exchanged between computer system 800 and other devices attached to a network 800, such as other computer systems, communications devices, control mechanisms, readers, scanners and so on that are components of a robotic induction technique and/or of a non-linear, unit-level materials handling system that implements the robotic induction technique. The communications channels may include, but are not limited to conventional and mobile telephone and text messaging communications channels. Network interface 840 may commonly support one or more wireless networking protocols (e.g., Wi-Fi/IEEE 802.11, or another wireless networking standard). However, in various embodiments, network interface 840 may support communication via any suitable wired or wireless general data networks, such as other types of Ethernet network, for example. Additionally, network interface 840 may support communication via telecommunications/telephony networks such as analog voice networks or digital fiber communications networks, via storage area networks such as Fibre Channel SANs, or via any other suitable type of network and/or protocol.

In some embodiments, system memory 820 may be one embodiment of a computer-accessible medium configured to store program instructions and data as described above for FIGS. 1 through 7 for implementing a control system for, or possibly other components of, modular material handling in a fulfillment center. However, in other embodiments, program instructions and/or data may be received, sent or stored upon different types of computer-accessible media. Generally speaking, a computer-accessible medium may include storage media or memory media such as magnetic or optical media, e.g., disk or DVD/CD coupled to computer system 800 via I/O interface 830. A computer-accessible medium may also include any volatile or non-volatile media such as RAM (e.g. SDRAM, DDR SDRAM, RDRAM, SRAM, etc.), ROM, etc, that may be included in some embodiments of computer system 800 as system memory 820 or another type of memory. Further, a computer-accessible medium may include transmission media or signals such as electrical, electromagnetic, or digital signals, conveyed via a communication medium such as a network and/or a wireless link, such as may be implemented via network interface 840.

Various embodiments may further include receiving, sending or storing instructions and/or data implemented in accordance with the foregoing description upon a computer-accessible medium. Generally speaking, a computer-accessible medium may include storage media or memory media such as magnetic or optical media, e.g., disk or DVD/CD-ROM, volatile or non-volatile media such as RAM (e.g. SDRAM, DDR, RDRAM, SRAM, etc.), ROM, etc., as well as transmission media or signals such as electrical, electromagnetic, or digital signals, conveyed via a communication medium such as network and/or a wireless link.

The various methods as illustrated in the Figures and described herein represent exemplary embodiments of methods. The methods may be implemented in software, hardware, or a combination thereof. The order of method may be changed, and various elements may be added, reordered, combined, omitted, modified, etc.

Various modifications and changes may be made as would be obvious to a person skilled in the art having the benefit of this disclosure. It is intended that the invention embrace all such modifications and changes and, accordingly, the above description to be regarded in an illustrative rather than a restrictive sense. 

What is claimed is:
 1. An order fulfillment system, comprising: inventory storage, comprising two inventory storage areas; a processing area disposed between the two inventory storage areas, wherein a conveyance mechanism conveys conveyance receptacles holding inventory items from the inventory storage to the processing area, and wherein the conveyance receptacles are not fixed to the conveyance mechanism; the processing area configured to receive inventory items from the two inventory storage areas and to process the received inventory items for shipment, wherein the processing area comprises a router module configured to route items received from inventory storage to a plurality of different processing modules; a receiving module corresponding to at least one of the two inventory storage areas and configured to receive replenishment inventory into the order fulfillment system; and a control system implemented by one or more computer processors and configured to direct conveyance of a replenishment supply of an inventory item from the receiving module to one or more inventory storage zones of the corresponding inventory storage area for storing the replenishment supply.
 2. The order fulfillment system of claim 1, wherein the one or more inventory storage zones for storing the replenishment supply are determined based at least in part on optimization criteria.
 3. The order fulfillment system of claim 2, where the optimization criteria is based at least in part on at least one of inventory throughput, cost, or storage density.
 4. The order fulfillment system of claim 1, wherein to direct conveyance of the replenishment supply from the receiving module to one or more inventory storage zones of the corresponding inventory storage area, the control system is further configured to direct the conveyance mechanism to convey the replenishment supply from the receiving module to the one or more inventory storage zones of the corresponding inventory storage area such that the same conveyance mechanism that conveys the receptacles to the processing area also conveys the replenishment supply to the one or more inventory storage zones.
 5. The order fulfillment system of claim 1, wherein to direct conveyance of the replenishment supply from the receiving module to one or more inventory storage zones of the corresponding inventory storage area, the control system is further configured to direct conveyance of the replenishment supply from the receiving module to a replenishment sorter between the receiving module and the one or more inventory storage zones, the replenishment sorter controlled by the control system to sort the replenishment supply such that storage of the replenishment supply is optimized based at least in part on minimization of pick or stow times.
 6. A computing system, comprising: one or more processors; and memory, coupled to the one or more processors, having instructions stored thereon that in response to execution by the one or more processors implement a control system configured to: determine one or more inventory storage zones of one of two inventory storage areas of a facility, the determined inventory storage zones for storing a replenishment supply of inventory items, and the facility comprising a processing area disposed between the two inventory storage areas, wherein the processing area is configured to receive inventory items from the two inventory storage areas and to process the received inventory items for shipment, and wherein the processing area disposed between the two inventory storage areas comprises a router module configured to route items received from inventory storage to a plurality of different processing modules; and direct a conveyance mechanism to convey the replenishment supply from a receiving module of the facility to the determined one or more inventory storage zones; wherein a conveyance mechanism conveys conveyance receptacles holding inventory items from inventory storage to the processing area, and wherein the conveyance receptacles are not fixed to the conveyance mechanism.
 7. The computing system of claim 6, wherein the one or more inventory storage zones for storing the replenishment supply are determined based at least in part on optimization criteria.
 8. The computing system of claim 7, where the optimization criteria is based at least in part on at least one of item throughput, cost, or storage density.
 9. The computing system of claim 6, wherein the conveyance mechanism that conveys the receptacles to the processing area is the same conveyance mechanism that conveys the replenishment supply from the receiving module.
 10. The computing system of claim 6, wherein to direct the replenishment supply from the receiving module to the determined one or more inventory storage zones, the control system is further configured to direct conveyance of the replenishment supply from the receiving module to a replenishment sorter between the receiving module and the determined one or more inventory storage zones, the control system further configured to direct the replenishment sorter to sort the replenishment supply prior to conveyance to the one or more inventory storage zones.
 11. The computing system of claim 6, wherein the control system is further configured to direct a conveyance mechanism to convey another replenishment supply of an inventory item from another receiving module of the facility to one or more inventory storage zones of the other of the two inventory storage areas.
 12. A method, comprising: determining one or more inventory storage zones of one of two inventory storage areas of a facility, the one or more inventory storage zones determined for storing a replenishment supply of inventory items, and the facility comprising a processing area disposed between the two inventory storage areas, wherein the processing area is configured to receive inventory items from the two inventory storage areas and to process the received inventory items for shipment, and wherein the processing area disposed between the two inventory storage areas comprises a router module configured to route items received from inventory storage to a plurality of different processing modules; and directing a conveyance mechanism to convey the replenishment supply from a receiving module of the facility to the determined one or more inventory storage zones; wherein a conveyance mechanism conveys conveyance receptacles holding inventory items from inventory storage to the processing area, and wherein the conveyance receptacles are not fixed to the conveyance mechanism.
 13. The method of claim 12, wherein the one or more inventory storage zones for storing the replenishment supply are determined based at least in part on optimization criteria.
 14. The method of claim 13, where the optimization criteria is based at least in part on at least one of inventory item throughput, cost, or storage density.
 15. The method of claim 12 wherein the conveyance mechanism that conveys the replenishment supply from the receiving module to the determined one or more inventory storage zones is the same conveyance mechanism that conveys conveyance receptacles from inventory storage to the processing area.
 16. The method of claim 12, wherein said directing the replenishment supply from the receiving module to the determined one or more inventory storage zones comprises directing conveyance of the replenishment supply from the receiving module to a replenishment sorter between the receiving module and the determined one or more inventory storage zones, and wherein the method further comprises sorting the replenishment supply by the replenishment sorter prior to conveyance of the replenishment supply to the one or more inventory storage zones.
 17. The method of claim 12, wherein the method further comprises directing a conveyance mechanism to convey another replenishment supply of an inventory item from another receiving module of the facility to one or more inventory storage zones of the other of the two inventory storage areas.
 18. The method of claim 12, further comprising directing storage of the replenishment supply to the determined one or more inventory storage zones. 